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41.
GaAs器件工艺中等离子刻蚀及计算机辅助监控技术研究 总被引:2,自引:1,他引:1
陈正明 《固体电子学研究与进展》1994,14(2):182-185
用N2气和NF3反应气体,在较低的刻蚀功率下实现了用薄正性光刻胶AZ1518作掩模,均匀、快速刻蚀SiO2,SiON,Si3N4,WN,W等材料的等离子刻蚀技术。利用到蚀过程中射频参数的变化和计算机技术,将射频参数的变化在计算机屏幕上实时显示,实现了计算机辅助监控和终点检测技术。 相似文献
42.
Measurement selection for parametric IC fault diagnosis 总被引:1,自引:0,他引:1
This article presents experimental results which show feedforward neural networks are well-suited for analog IC fault diagnosis. Boundary band data (BBD) measurement selection is used to reduce the computational overhead of the FFN training phase. We compare the diagnostic accuracy between traditional statistical classifiers and feedforward neural networks trained with various measurement selection criteria. The feedforward networks consistently perform as well as or better than the other classifiers in term of accuracy. Training using BBD consistently reduces the FFN training efforts without degrading the performance. Experimental results suggest that feedforward networks provide a cost efficient method for IC fault diagnosis in a large scale production testing environment.This work is supported by NSF-IUC CDADIC, Project 90-1. 相似文献
43.
通过对3G的市场分析、技术分析、制式选择关键因素分析和经济分析,得出了中国新移动运营商3G的发展策略。无论从基于频率资源与制式关系的考虑,基于选择3G主流制式的考虑,还是从基于利用非对称频段资源、采用TD-SCDMA混合组网的考虑,对新的运营商来说,采用WCDMA来建设移动通信系统都是必要和有利的选择。 相似文献
44.
网上协作学习模式研究 总被引:1,自引:0,他引:1
主要针对网上协作学习的基本模式、实现方式和存在的问题进行了初步研究。 相似文献
45.
随着数字技术和计算机技术的发展,非线性编辑系统已经越来越广泛地应用在电视节目制作中.阐述了非线性编辑系统在电视新闻节目(包括新闻专题节目、以新闻消息为主的日播节目等)制作中具有的优势和存在的劣势. 相似文献
46.
本文较系统、通俗地介绍了模拟视频特技切换台的矩阵输入、混合/效果放大器(M/E)、下游键、系统控制和同步发生器等电路单元,介绍了特技切换台的切换、混合、扫变、键控的基本原理和功能。 相似文献
47.
T. Drglin 《Accreditation and quality assurance》2003,8(3-4):130-133
A validation procedure based on the ISO/IEC 17025 standard was used to demonstrate the long-term stability of a calibration
process and to assess the measurement uncertainty of a standard test method for optical emission vacuum spectrometric analysis
of carbon and low-alloy steel (ASTM E 415–99a). The validation was used to provide documented evidence that the selected method
fulfils the requirements and that the method is ”fit for purpose”. A test for drift was applied to determine statistically
whether the analytical results vary systematically with time. The accuracy and traceability of the optimised method were tested
by an analysis of closely matched matrix certified reference materials (CRMs). The measurement uncertainty estimations took
account of the precision study, the bias and its uncertainty, and the qualification of uncertainties not considered in the
overall performance studies.
Received: 2 November 2002 Accepted: 2 January 2003
Acknowledgement The author expresses gratitude to Dr. Aleš Fajgelj for helpful discussions during the 3rd Central European Conference on Reference Materials and Measurements.
Presented at CERMM-3, Central European Reference Materials and Measurements Conference: The function of reference materials
in the measurement process, May 30–June 1, 2002, Rogaška Slatina, Slovenia
Correspondence to T. Drglin 相似文献
48.
Implementation and experimental study on fast object modeling based on multiple structured stripes 总被引:6,自引:0,他引:6
In this paper, a practical structured light-based system for fast object modeling and reconstruction is reported. The system consists of an off-the-shelf digital projector, a video camera and a turntable. The system calibration is implemented accurately and automatically by taking a single image of an illuminated calibration template. The multiple color light stripes emitted by the projector adopt only three colors and the color can be modified easily according to the surface texture of the object. This makes the system widely applicable in many situations, and the assumption about color neutrality, which is a limitation to other similar systems, can be largely relaxed. The registration and merging algorithm is greatly simplified by employing a turntable. The validity and high accuracy of the method are demonstrated by extensive real experiments. 相似文献
49.
An analytical result is not considered to be complete without a statement of the measurement uncertainty associated with
it. Evaluation of measurement uncertainty is therefore an essential part of every determination. In the present study the
measurement uncertainty of the result of determination of selenium in the reference material Seronorm Trace Elements Serum
was studied. The combination of a digestion procedure using sulfuric acid, V2O5 in H2SO4 and hydrogen peroxide and the continuous flow approach of hydride generation atomic fluorescence spectrometry (HG-AFS) detection
was used for selenium determination. The total uncertainty budget was calculated with the help of the GUM Workbench program,
in which computations follow the rules of the ’ISO guide to the expression of uncertainty in measurement’. The major sources
of uncertainty were found to be due to the recovery of the procedure, measurement of peak heights and the purity of Na2SeO3. A selenium mass fraction of 77.1±4.8 ng/g (with a coverage factor of 2.1, 95% probability) was determined, which is comparable
with the recommended value of 80 ng/g.
Received: 13 September 2002 Accepted: 23 December 2002
Acknowledgements We would like to thank Tinkara Buˇcar, B.Sc. for useful discussions and the IAEA Vienna, for financial support of the project
11553/RO.
Presented at CERMM-3, Central European Reference Materials and Measurements Conference: The function of reference materials
in the measurement process, May 30–June 1, 2002, Rogaška Slatina, Slovenia
Correspondence to V. Stibilj 相似文献
50.
DING Xuantong YANG Qingwei YAN Long wen LIU Yi HUANG Yuan LIU Zetian HONG Wenyu SHI Peilan 《核工业西南物理研究院年报(英文版)》2004,(1):1-4
The main mission the HL-2A tokamak is of the experiments on to explore the divertor physics and to investigate the plasma confinement, transport and instabilities with high power auxiliary heating and advanced fuelling, it is necessary to develop more new diagnostics and increase the spatial and temporal resolutions of the measurements for exist system. Up to now, about 30 diagnostic systems have been moved from HL-1M to HL-2A tokamak. Other 10 diagnostic systems are being designed and installed on the device. In developed in last 2 years, will be presented. 相似文献